Woodland Vole (Microtus pinetorum)

County List:

Rule:

Forested or Mixed Forested/Nonforested Landscapes

      (Oak (Sm Saw or Lg Saw or Uneven))
      or (Assorted Hardwoods (Sm Saw or Lg Saw or Uneven))
      or (Northern Hardwoods (Sm Saw or Lg Saw or Uneven))
      or (Mixed Northern Hardwoods (Sm Saw or Lg Saw or Uneven))
      or (Mixed Upland Hardwoods (Sm Saw or Lg Saw or Uneven))
      or (Bottomland Hardwoods (Sm Saw or Lg Saw or Uneven))
      or Savanna
   containing:
      Dead Down Woody Debris

Habitat List:

view size class definitions

Literature:

Unlike the meadow or prairie vole, the woodland vole inhabits a variety of forested areas. This species prefers hardwood forests of oak, maple, and beech, although it is a potential resident of any wooded area-deciduous, coniferous, or mixed. It occasionally lives in orchards and becomes a pest by girdling trees while feeding on bark. This vole is semifossorial, and its burrowing habits require a well-drained sandy soil overlain by a thick layer of duff.

This mammal sometimes hides its nest under a log or among tree roots but usually places it at the end of an underground passage.

As suggested by its burrowing habits, a woodland vole feeds extensively on roots, tubers, and rhizomes throughout the year. In summer, it adds clover sprouts, grass stems, fruits, seeds, and nuts. In autumn, it caches tubers and stems in a subterranean chamber for use in winter and often resorts to eating bark before spring arrives. The woodland vole, as well as the meadow vole, practices coprophagy, especially when forced to rely on low-quality foods.

Habitat: Deciduous forests, grasslands, meadows, and orchards. Occurs in marshes and swamps but favors well-drained uplands.

Special Habitat Requirements: May require ground-cover of leaves (duff) or grass; moist well-drained soils.

Habitat Preferences: The woodland vole is commonly associated with mature hardwood forests where there are loose, sandy soils and deep humus suitable for burrowing. It is also fond of grassy areas in park-like stands of orchard trees, on hillsides, along fence-rows, and in road right-of-ways. Of the less than 100 specimens captured in Michigan, most were taken in open or closed wooded areas, characterized by oak-maple, oak-hickory, oak-hickory-maple-beech, maple-ash- maple-beech, fir-spruce, floodplain growth, and orchards. For these habitats to be suitable for woodland voles, there needs to be a thick layer of loose soil and humus with fallen leaves or rank grass cover. In Clinton County, Linduska found woodland voles in an ungrazed woodlot and under field-shocked corn in winter. A repetition of this trapping program almost 40 years later by Shier failed to reveal any of these rodents. In Charlevoix County, Dice caught one animal in wet, second-growth fir and spruce forest. In Berrien County, Dice captured woodland voles under leaf litter in mature beech-maple and floodplain woods. In Kalamazoo County, Allen found two woodland voles in a basement.

In other parts of its range the woodland vole shows remarkable ability to thrive in diverse woodland habitats. In New Jersey, Pearson found the species to be associated with perennial forbs in early successional stages of vegetative growth and also with shrub tree cover in late stages. These voles have been found in pine plantations, damp sphagnum, and cranberry bogs; in upland woods; on rocky hills; in open sandy field and apple orchards; in pine-oak woods; in well-drained uplands but also in swamps; in pine-hardwood forest and woodland edges; and within the root systems of large trees.

Behavior: Woodland voles usually construct their nests below ground at depths up to 12 inches. On occasion, nests can be found at locations only slightly below the surface, under logs, stumps, and debris. In orchards, nests are often placed just below ground among roots or next to tree trunks.

Food Habits: As a consequence of its preference for living in underground burrows, the woodland vole relies on succulent tubers and roots as a major part of its food supply. Observers have reported underground caches of tubers and fruits of such plants as wild violet, white clover, red haw, Dutchman's britches, wild morning glory, quack grass, broad-leaf dock, wild onion, acorns, hickory nuts, and hazelnuts. Stores are accumulated in autumn, presumably for winter use. As a result, according to Jackson, woodland voles do not subsist on green vegetation to the extent that meadow voles and prairie voles do. Like these other voles, however, the woodland voles also eats a variety of ground-living insects, their larvae and other invertebrates; it is also known to be cannibalistic. Woodland voles like the bark from roots and bases of trees and shrubs, and roots and bulbs of garden plantings.

Ecology: Populations of Microtus pinetorum occur in a wide variety of habitats throughout their range, varying from subclimax beech-maple forests with closed canopies and varying depths of leaf litter to grassy fields with many bushes, patches of brambles, and mats of honeysuckle. Well drained soil with a thick ground cover of either litter of vegetation are common parameters in most habitat descriptions. Floral assemblages consisting of beech, red maple, red oak, black oak, and white oak were reported for pine voles collected in Vermont and Connecticut.

The floral assemblage in the northern Midwestern portion of the range consists of maple, elm, yellow birch, basswood, ferns in Wisconsin; grasses and honeysuckle in Illinois; and hickory in Michigan. Standing water is not a requirement for pine voles since they can subsist on dietary water contained in succulent vegetation.

The restriction of M. pinetorum to dry habitats is undoubtedly related to its semifossorial habits. Microtus pinetorum could not occupy subsurface runways in areas where the substrate is saturated for significant periods of time. Similarly, surface humidity should have little influence on its distribution; positive association with surface vegetation cover was not observed.